Abstract: A design scheme of bus-based servo drive controller and system reconfiguration for the satellite retroaction flywheel was investigated.In this scheme,a reliable power inverter as well as a pumped voltage suppresser was constructed,and a magnetic induction sensor was developed to monitor the three-phase motor currents.Besides,only six Hall-effect latches,half of which were backups,were used to control commutation and measure the speed with improved M/T algorithm.IP cores and system level ASIC of the full-digital servo controller were completed based on field bus protocol,integrated with a redundant reconfiguration manager as well as multiple reconstruction techniques.This system-on-chip of flywheel controller was implemented on an FPGA platform.Experimental results indicate that the designed system can provide satisfactory dynamic and static performances throughout the whole four quadrants.